Populations with a low incidence of cancer of the colon (Africans, Indians and Japanese) consume a low fat diet, have differences in their fecal microflora, and fecal acid and neutral steroids excretion when compared to populations with a high incidence of colon cancer. Although groups of patients from these geographic areas have been compared, there has been no comparison made within a high incidence area of colon cancer among different groups for these factors. The object of this study is to do a detailed diet evaluation, fecal quantitative and qualitative anaerobic and aerobic flora, and fecal steroid excretion among patients with colon cancer (before and after surgery), and normals in high incidence areas of colon cancer in Connecticut. It is hoped that this evaluation will reveal whether the diet and microflora have any significant role in colon carcinogenesis.